gui: Replace interface::Node references with pointers

No change in behavior. Replacing references with pointers allows Node interface
creation to be delayed until later during gui startup next commit to support
implementing -ipcconnect option

9 files changed, 74 insertions, 41 deletions

diff --git a/src/qt/bitcoin.cpp b/src/qt/bitcoin.cpp
index 3616fbd50a..01799f34df 100644
--- a/src/qt/bitcoin.cpp
+++ b/src/qt/bitcoin.cpp
@@ -196,10 +196,9 @@ void BitcoinCore::shutdown()
 static int qt_argc = 1;
 static const char* qt_argv = "bitcoin-qt";
 
-BitcoinApplication::BitcoinApplication(interfaces::Node& node):
+BitcoinApplication::BitcoinApplication():
     QApplication(qt_argc, const_cast<char **>(&qt_argv)),
     coreThread(nullptr),
-    m_node(node),
     optionsModel(nullptr),
     clientModel(nullptr),
     window(nullptr),
@@ -249,12 +248,13 @@ void BitcoinApplication::createPaymentServer()
 
 void BitcoinApplication::createOptionsModel(bool resetSettings)
 {
-    optionsModel = new OptionsModel(m_node, this, resetSettings);
+    optionsModel = new OptionsModel(this, resetSettings);
+    optionsModel->setNode(node());
 }
 
 void BitcoinApplication::createWindow(const NetworkStyle *networkStyle)
 {
-    window = new BitcoinGUI(m_node, platformStyle, networkStyle, nullptr);
+    window = new BitcoinGUI(node(), platformStyle, networkStyle, nullptr);
 
     pollShutdownTimer = new QTimer(window);
     connect(pollShutdownTimer, &QTimer::timeout, window, &BitcoinGUI::detectShutdown);
@@ -262,17 +262,25 @@ void BitcoinApplication::createWindow(const NetworkStyle *networkStyle)
 
 void BitcoinApplication::createSplashScreen(const NetworkStyle *networkStyle)
 {
-    SplashScreen *splash = new SplashScreen(m_node, nullptr, networkStyle);
+    assert(!m_splash);
+    m_splash = new SplashScreen(nullptr, networkStyle);
+    m_splash->setNode(node());
     // We don't hold a direct pointer to the splash screen after creation, but the splash
     // screen will take care of deleting itself when finish() happens.
-    splash->show();
-    connect(this, &BitcoinApplication::splashFinished, splash, &SplashScreen::finish);
-    connect(this, &BitcoinApplication::requestedShutdown, splash, &QWidget::close);
+    m_splash->show();
+    connect(this, &BitcoinApplication::splashFinished, m_splash, &SplashScreen::finish);
+    connect(this, &BitcoinApplication::requestedShutdown, m_splash, &QWidget::close);
+}
+
+void BitcoinApplication::setNode(interfaces::Node& node)
+{
+    assert(!m_node);
+    m_node = &node;
 }
 
 bool BitcoinApplication::baseInitialize()
 {
-    return m_node.baseInitialize();
+    return node().baseInitialize();
 }
 
 void BitcoinApplication::startThread()
@@ -280,7 +288,7 @@ void BitcoinApplication::startThread()
     if(coreThread)
         return;
     coreThread = new QThread(this);
-    BitcoinCore *executor = new BitcoinCore(m_node);
+    BitcoinCore *executor = new BitcoinCore(node());
     executor->moveToThread(coreThread);
 
     /*  communication to and from thread */
@@ -334,7 +342,7 @@ void BitcoinApplication::requestShutdown()
     window->unsubscribeFromCoreSignals();
     // Request node shutdown, which can interrupt long operations, like
     // rescanning a wallet.
-    m_node.startShutdown();
+    node().startShutdown();
     // Unsetting the client model can cause the current thread to wait for node
     // to complete an operation, like wait for a RPC execution to complete.
     window->setClientModel(nullptr);
@@ -356,7 +364,7 @@ void BitcoinApplication::initializeResult(bool success, interfaces::BlockAndHead
     {
         // Log this only after AppInitMain finishes, as then logging setup is guaranteed complete
         qInfo() << "Platform customization:" << platformStyle->getName();
-        clientModel = new ClientModel(m_node, optionsModel);
+        clientModel = new ClientModel(node(), optionsModel);
         window->setClientModel(clientModel, &tip_info);
 #ifdef ENABLE_WALLET
         if (WalletModel::isWalletEnabled()) {
@@ -456,7 +464,8 @@ int GuiMain(int argc, char* argv[])
     QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
 #endif
 
-    BitcoinApplication app(*node);
+    BitcoinApplication app;
+    app.setNode(*node);
 
     /// 2. Parse command-line options. We do this after qt in order to show an error if there are problems parsing these
     // Command-line options take precedence:
@@ -612,10 +621,10 @@ int GuiMain(int argc, char* argv[])
         }
     } catch (const std::exception& e) {
         PrintExceptionContinue(&e, "Runaway exception");
-        app.handleRunawayException(QString::fromStdString(node->getWarnings().translated));
+        app.handleRunawayException(QString::fromStdString(app.node().getWarnings().translated));
     } catch (...) {
         PrintExceptionContinue(nullptr, "Runaway exception");
-        app.handleRunawayException(QString::fromStdString(node->getWarnings().translated));
+        app.handleRunawayException(QString::fromStdString(app.node().getWarnings().translated));
     }
     return rv;
 }
diff --git a/src/qt/bitcoin.h b/src/qt/bitcoin.h
index 20c6dfc047..69e0a5921e 100644
--- a/src/qt/bitcoin.h
+++ b/src/qt/bitcoin.h
@@ -10,6 +10,7 @@
 #endif
 
 #include <QApplication>
+#include <assert.h>
 #include <memory>
 
 #include <interfaces/node.h>
@@ -20,6 +21,7 @@ class NetworkStyle;
 class OptionsModel;
 class PaymentServer;
 class PlatformStyle;
+class SplashScreen;
 class WalletController;
 class WalletModel;
 
@@ -54,7 +56,7 @@ class BitcoinApplication: public QApplication
 {
     Q_OBJECT
 public:
-    explicit BitcoinApplication(interfaces::Node& node);
+    explicit BitcoinApplication();
     ~BitcoinApplication();
 
 #ifdef ENABLE_WALLET
@@ -88,6 +90,9 @@ public:
     /// Setup platform style
     void setupPlatformStyle();
 
+    interfaces::Node& node() const { assert(m_node); return *m_node; }
+    void setNode(interfaces::Node& node);
+
 public Q_SLOTS:
     void initializeResult(bool success, interfaces::BlockAndHeaderTipInfo tip_info);
     void shutdownResult();
@@ -102,7 +107,6 @@ Q_SIGNALS:
 
 private:
     QThread *coreThread;
-    interfaces::Node& m_node;
     OptionsModel *optionsModel;
     ClientModel *clientModel;
     BitcoinGUI *window;
@@ -114,6 +118,8 @@ private:
     int returnValue;
     const PlatformStyle *platformStyle;
     std::unique_ptr<QWidget> shutdownWindow;
+    SplashScreen* m_splash = nullptr;
+    interfaces::Node* m_node = nullptr;
 
     void startThread();
 };
diff --git a/src/qt/optionsmodel.cpp b/src/qt/optionsmodel.cpp
index f7c54f7892..7e089b4f95 100644
--- a/src/qt/optionsmodel.cpp
+++ b/src/qt/optionsmodel.cpp
@@ -27,8 +27,8 @@ const char *DEFAULT_GUI_PROXY_HOST = "127.0.0.1";
 
 static const QString GetDefaultProxyAddress();
 
-OptionsModel::OptionsModel(interfaces::Node& node, QObject *parent, bool resetSettings) :
-    QAbstractListModel(parent), m_node(node)
+OptionsModel::OptionsModel(QObject *parent, bool resetSettings) :
+    QAbstractListModel(parent)
 {
     Init(resetSettings);
 }
@@ -353,7 +353,7 @@ bool OptionsModel::setData(const QModelIndex & index, const QVariant & value, in
             break;
         case MapPortUPnP: // core option - can be changed on-the-fly
             settings.setValue("fUseUPnP", value.toBool());
-            m_node.mapPort(value.toBool());
+            node().mapPort(value.toBool());
             break;
         case MinimizeOnClose:
             fMinimizeOnClose = value.toBool();
diff --git a/src/qt/optionsmodel.h b/src/qt/optionsmodel.h
index 14fdf9046e..3d9e7bbb80 100644
--- a/src/qt/optionsmodel.h
+++ b/src/qt/optionsmodel.h
@@ -11,6 +11,8 @@
 
 #include <QAbstractListModel>
 
+#include <assert.h>
+
 namespace interfaces {
 class Node;
 }
@@ -39,7 +41,7 @@ class OptionsModel : public QAbstractListModel
     Q_OBJECT
 
 public:
-    explicit OptionsModel(interfaces::Node& node, QObject *parent = nullptr, bool resetSettings = false);
+    explicit OptionsModel(QObject *parent = nullptr, bool resetSettings = false);
 
     enum OptionID {
         StartAtStartup,         // bool
@@ -92,10 +94,11 @@ public:
     void setRestartRequired(bool fRequired);
     bool isRestartRequired() const;
 
-    interfaces::Node& node() const { return m_node; }
+    interfaces::Node& node() const { assert(m_node); return *m_node; }
+    void setNode(interfaces::Node& node) { assert(!m_node); m_node = &node; }
 
 private:
-    interfaces::Node& m_node;
+    interfaces::Node* m_node = nullptr;
     /* Qt-only settings */
     bool fHideTrayIcon;
     bool fMinimizeToTray;
diff --git a/src/qt/splashscreen.cpp b/src/qt/splashscreen.cpp
index 6e6b2b8466..50fe8eb28b 100644
--- a/src/qt/splashscreen.cpp
+++ b/src/qt/splashscreen.cpp
@@ -24,8 +24,8 @@
 #include <QScreen>
 
 
-SplashScreen::SplashScreen(interfaces::Node& node, Qt::WindowFlags f, const NetworkStyle *networkStyle) :
-    QWidget(nullptr, f), curAlignment(0), m_node(node)
+SplashScreen::SplashScreen(Qt::WindowFlags f, const NetworkStyle *networkStyle) :
+    QWidget(nullptr, f), curAlignment(0)
 {
     // set reference point, paddings
     int paddingRight            = 50;
@@ -124,7 +124,6 @@ SplashScreen::SplashScreen(interfaces::Node& node, Qt::WindowFlags f, const Netw
     setFixedSize(r.size());
     move(QGuiApplication::primaryScreen()->geometry().center() - r.center());
 
-    subscribeToCoreSignals();
     installEventFilter(this);
 
     GUIUtil::handleCloseWindowShortcut(this);
@@ -132,14 +131,26 @@ SplashScreen::SplashScreen(interfaces::Node& node, Qt::WindowFlags f, const Netw
 
 SplashScreen::~SplashScreen()
 {
-    unsubscribeFromCoreSignals();
+    if (m_node) unsubscribeFromCoreSignals();
+}
+
+void SplashScreen::setNode(interfaces::Node& node)
+{
+    assert(!m_node);
+    m_node = &node;
+    subscribeToCoreSignals();
+}
+
+void SplashScreen::shutdown()
+{
+    if (m_node) m_node->startShutdown();
 }
 
 bool SplashScreen::eventFilter(QObject * obj, QEvent * ev) {
     if (ev->type() == QEvent::KeyPress) {
         QKeyEvent *keyEvent = static_cast<QKeyEvent *>(ev);
         if (keyEvent->key() == Qt::Key_Q) {
-            m_node.startShutdown();
+            shutdown();
         }
     }
     return QObject::eventFilter(obj, ev);
@@ -183,10 +194,10 @@ void SplashScreen::ConnectWallet(std::unique_ptr<interfaces::Wallet> wallet)
 void SplashScreen::subscribeToCoreSignals()
 {
     // Connect signals to client
-    m_handler_init_message = m_node.handleInitMessage(std::bind(InitMessage, this, std::placeholders::_1));
-    m_handler_show_progress = m_node.handleShowProgress(std::bind(ShowProgress, this, std::placeholders::_1, std::placeholders::_2, std::placeholders::_3));
+    m_handler_init_message = m_node->handleInitMessage(std::bind(InitMessage, this, std::placeholders::_1));
+    m_handler_show_progress = m_node->handleShowProgress(std::bind(ShowProgress, this, std::placeholders::_1, std::placeholders::_2, std::placeholders::_3));
 #ifdef ENABLE_WALLET
-    m_handler_load_wallet = m_node.handleLoadWallet([this](std::unique_ptr<interfaces::Wallet> wallet) { ConnectWallet(std::move(wallet)); });
+    m_handler_load_wallet = m_node->handleLoadWallet([this](std::unique_ptr<interfaces::Wallet> wallet) { ConnectWallet(std::move(wallet)); });
 #endif
 }
 
@@ -221,6 +232,6 @@ void SplashScreen::paintEvent(QPaintEvent *event)
 
 void SplashScreen::closeEvent(QCloseEvent *event)
 {
-    m_node.startShutdown(); // allows an "emergency" shutdown during startup
+    shutdown(); // allows an "emergency" shutdown during startup
     event->ignore();
 }
diff --git a/src/qt/splashscreen.h b/src/qt/splashscreen.h
index 3158524117..dc394ac439 100644
--- a/src/qt/splashscreen.h
+++ b/src/qt/splashscreen.h
@@ -28,8 +28,9 @@ class SplashScreen : public QWidget
     Q_OBJECT
 
 public:
-    explicit SplashScreen(interfaces::Node& node, Qt::WindowFlags f, const NetworkStyle *networkStyle);
+    explicit SplashScreen(Qt::WindowFlags f, const NetworkStyle *networkStyle);
     ~SplashScreen();
+    void setNode(interfaces::Node& node);
 
 protected:
     void paintEvent(QPaintEvent *event) override;
@@ -50,6 +51,8 @@ private:
     void subscribeToCoreSignals();
     /** Disconnect core signals to splash screen */
     void unsubscribeFromCoreSignals();
+    /** Initiate shutdown */
+    void shutdown();
     /** Connect wallet signals to splash screen */
     void ConnectWallet(std::unique_ptr<interfaces::Wallet> wallet);
 
@@ -58,7 +61,7 @@ private:
     QColor curColor;
     int curAlignment;
 
-    interfaces::Node& m_node;
+    interfaces::Node* m_node = nullptr;
     std::unique_ptr<interfaces::Handler> m_handler_init_message;
     std::unique_ptr<interfaces::Handler> m_handler_show_progress;
     std::unique_ptr<interfaces::Handler> m_handler_load_wallet;
diff --git a/src/qt/test/addressbooktests.cpp b/src/qt/test/addressbooktests.cpp
index 035c8196bc..84f981dff3 100644
--- a/src/qt/test/addressbooktests.cpp
+++ b/src/qt/test/addressbooktests.cpp
@@ -108,7 +108,7 @@ void TestAddAddressesToSendBook(interfaces::Node& node)
 
     // Initialize relevant QT models.
     std::unique_ptr<const PlatformStyle> platformStyle(PlatformStyle::instantiate("other"));
-    OptionsModel optionsModel(node);
+    OptionsModel optionsModel;
     ClientModel clientModel(node, &optionsModel);
     AddWallet(wallet);
     WalletModel walletModel(interfaces::MakeWallet(wallet), clientModel, platformStyle.get());
diff --git a/src/qt/test/test_main.cpp b/src/qt/test/test_main.cpp
index 2ffb452ade..86356b43c8 100644
--- a/src/qt/test/test_main.cpp
+++ b/src/qt/test/test_main.cpp
@@ -68,10 +68,11 @@ int main(int argc, char* argv[])
 
     // Don't remove this, it's needed to access
     // QApplication:: and QCoreApplication:: in the tests
-    BitcoinApplication app(*node);
+    BitcoinApplication app;
+    app.setNode(*node);
     app.setApplicationName("Bitcoin-Qt-test");
 
-    node->context()->args = &gArgs;     // Make gArgs available in the NodeContext
+    app.node().context()->args = &gArgs;     // Make gArgs available in the NodeContext
     AppTests app_tests(app);
     if (QTest::qExec(&app_tests) != 0) {
         fInvalid = true;
@@ -80,7 +81,7 @@ int main(int argc, char* argv[])
     if (QTest::qExec(&test1) != 0) {
         fInvalid = true;
     }
-    RPCNestedTests test3(*node);
+    RPCNestedTests test3(app.node());
     if (QTest::qExec(&test3) != 0) {
         fInvalid = true;
     }
@@ -89,11 +90,11 @@ int main(int argc, char* argv[])
         fInvalid = true;
     }
 #ifdef ENABLE_WALLET
-    WalletTests test5(*node);
+    WalletTests test5(app.node());
     if (QTest::qExec(&test5) != 0) {
         fInvalid = true;
     }
-    AddressBookTests test6(*node);
+    AddressBookTests test6(app.node());
     if (QTest::qExec(&test6) != 0) {
         fInvalid = true;
     }
diff --git a/src/qt/test/wallettests.cpp b/src/qt/test/wallettests.cpp
index 475fd589af..adcfe0d25c 100644
--- a/src/qt/test/wallettests.cpp
+++ b/src/qt/test/wallettests.cpp
@@ -163,7 +163,7 @@ void TestGUI(interfaces::Node& node)
     std::unique_ptr<const PlatformStyle> platformStyle(PlatformStyle::instantiate("other"));
     SendCoinsDialog sendCoinsDialog(platformStyle.get());
     TransactionView transactionView(platformStyle.get());
-    OptionsModel optionsModel(node);
+    OptionsModel optionsModel;
     ClientModel clientModel(node, &optionsModel);
     AddWallet(wallet);
     WalletModel walletModel(interfaces::MakeWallet(wallet), clientModel, platformStyle.get());